Manhole and bonnet for pipes and furnace-casings.



E. PANNENBORG. MANHOLE AND BONNET FOR PIPES AND FURNAGE OASINGS.

- APPLICATION TILLD MAR.24, 1909.

Patentd Sept. 21, 1909.

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Z M6 m m m m n a S 1% my M m e w m mfiwfllgxx. 2% H WITNESSES n 1 WW V E. PANNENBORG. MANHOLE AND BONNET FOR PIPES AND FURNACE GASINGS.

APPLICATION FILED MAILM, 1909.

Patented Sept. 21. 1909.

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" MI mlroa Eric/z Pazzrzezzarg rd WIN/E8858 By Mm ATTOR/VE VS renrcrnn er ERICH PANNENBGRG, 01 SYRACUSE, NEW YQRK.

IMANHOLE AND BOENET' FOR PIPES AND FU'RNACE-CASINGS.

Specification of Letters Patent. Pgrtjegnfgod Sept]. 21, llllil ll Application filed March 24, 1909. Serial No. 485,483.

" the following is a full. clear, and exact description.

it is well known that in the use of hot air furnaces and hot air conveying pipes there- 'for, line ashes and dust accumulate therein,

that must be removed at times, to permit the proper heating of inducted air and the free flow of the heated air to points of discharge therefor. Ordinarily the means for ali'ording access to hot air spaces that intervene between the exterior casing and inner wall of the furnace, is restricted to small hand holes, and the worlt of cleaning out the ashes or dust 1s diflicult. Further, to remove such accumulations from heat con- .reying pipes, their complete removal from the furnace casing is required, at an expenditure of considerable time and labor to detach and replace them.

The purpose of my present invention is. to provide novel details of construction for the formation of an ample inlet into hot air spaces in a furnace or a hot air conveying pipe, and for a bonnet for closing such an inlet, which will completely seal the same; and a. further object of the invention is to so construct the cover or bonnet for closure of an opening formed in a hot air furnace wall or a hot air pipe, that the material re moved inthe formation of such an opening will be used inthe production of a. bonnet or cover therefor and thus economize n1aterial.

The invention consists inthe novel construction and combination of parts, as is hereinafter deseriliejd and defined in the appended claims.

Reference is to be had to the accompanying drawings forming a part of this specification, in which similar characters of reference indicate corresponding parts in all the views.

Figure l is a. front view of one example of construction of the improvement applied for closure of an opening in a furnace casing or the like: Fig. 2 is a longitudinal scelional view. taken substantially on the line 2-2 ip Fig. 1; Fig. 3 is an enlarged transverse sectional view of details substantially on the line 3-4 in Fig. 1; Fig. l is a front view of the improved closure as applied. showing a slightly modified construction thereof: Fig. I) is a longitudinal sectional view, substantially on the line 5?) in Fig. el; and Fig. (3 is a transverse sectional view of details substantially on the line e e in Fig. l.

In the construction shown in Figs. 1. 3 and t). 5 indicates a portion of a hot air furnacc casing or exterior wall thcreof. said portion being rcprescntcd as a segment of a cylinder. but it is to be undcrsloml that the improvement is applicable to ornpon a Hat wall if this is desired. As is indicaled in Fig. l. a prcl'erably elongated rectangular aperture is formed in the casing wall 5. by cutting a corrcspondingly shaped portion 5 loosc therefrom. substantially on the dotted line 1/. (I. in said ligure. thus permitting free access into the annular space that is formed between the cylinder or fire chamber side wall. not shown. and the outer casing thereof. .i rectangular metal franie (5. cast or forged into shape constitutes a half section of the improved closure for the opening in the casing 5, it having such dimensions as permit it to lap evcnly upon the marginal portion of the casing wall defined by the line a u. when said frame is inserted withinihe rectangular opening and is'seatcd on said border portion of the casin having its convex side cngagcd with the corresponding concave inner surfacc of' said casing. As shown by dotted lines in Fig. 1. an ear' 7) is formed on each corner of the rectangular frame l). and pro iccts diagonally therefrom. these cars having a lapped engagement with the inner surface of the casing wall when the framc is placed in position thereon. The cars l) and the casing wall 5 are oppositely perforated and receive rivets c that are of -the inner corners of said outer frame-an inwardly projecting card is formed thereon, Tl e opening in the outer frame 7 is of such re ntive dimensions that a border portion 5 thereof will lap upon the corresponding portion of the rectangular cover plate that was cut loose from the casing 5. inthe formation of an opening therein. The inner concave surface of the outer border frame 7 con- 10 formsto the convex outersurt'ace of the cover plate 5, so that a tight joint will be formed between said surfaces where they are secured together. In the cars (l and cover plate .3, alined perforations are formed when the border frame T is -seated on the cover plate so that it laps evenly at its edges thereon,

-and in said perforations, rivets c are secured,

perforation is made that is disposed opposite a snmlar perforation m the inner border frame 6 and the casrng Wall 5, each of said through perforations receiving a bolt 8.

The perforation for the bolt 8, in each cornor of the inner border frame 6, 'is rectangular, and under the head 8 of each bolt 8, a

corresponding square portion is' formed on the bolt body, as is shown in Fig. 3, so that when each bolt is inserted in a respective 5 perforation from the inside outwardly, the threaded outer end thereof will project. sufficiently for the reception of a preferably winged nut 9. Two opposite projections g are formed on the inner side of the border frame (3, at each corner thereof, the pair of projections at each corner being disposed at opposite points near the head 8 of an in serted bolt 8, and in said projections that areoppositely perforated, a resilient wire rod /L is inserted and secured, said keepers by their engagement with the bolt heads preventing anaccidental displacement of the saine. It will be seen that the bolts 8.,when

in position, project beyond the outer surface,

ing the bolts in place when the outer border frame mounted thereon.

The construction of the improvement as represented in Figs. 4, 5' and (i, is substan tially similar to that hercinbefore described, the difference as shown, consisting in the employment of screw bolts and nuts 1', v," tor securing the inner border frame 10, upon a.

furnace casing 11. the bolts being preferably inserted in alined perforations formed at intervals in the casing and border frame from the outer side. .and the 1 s screwed in contact with the inner surf slof the inner border frame, as is clearly shown in Fig. 5. in the casing 11 by removal of a plate 11. '1 he outer border fraine 12 is of such dimensions that when in "position its edges Will have clearance from the heads of the bolts border frame 12 and the cover plate 11; to

1 this end, a thin asbestos joint-ring a may be i-placed between the opposed surfaces of the 2 frame 10 and casing 11, and a similar rmg a l l between the outer frame 12 and the cover t through binding the plates and frames upon the joint rings so as to renderthe joints airtight. The joint ring a, may be extended at its inner edge so that the edge port-ion of the cover plate 11 will be seated thereon. The bonnet for closure of the opening in the using ll, which consists of the plate 11 and border frame 12, isprcferably detachably secured on the casing 11, by four screw bolts 0, that are inserted through perforations in the outer border frame l2, and in alined perforations in the casing near each corner of the frame 12, these screw bolts engaging opposite threaded perforations in the corners of the inner border frame 10, as shown in Fig. 6. It is to be understood that if more than four clamping screws 0, are necessary, for the formation of air or fluid tight joints, between the border frames and a casing or thelike that receives. said closing means for an opening therein, any suitable number are to be provided.

. I do not desire to limit the application of the improvement to the closure of openings in furnace casings, as the same may be ap i plied for the closure of openings in Water or oil tanks, and other vessels wherein openings are formed. and I wish to reserve the right to apply the im n'ove'd closure wherecvcr it may be done with advantage.

The. accunmlations in hot air conveying pipes consist mainly of carpet. sweepings and dust from hall floors androoms, thatenter through registers and form coatings on the inner sides of such pipes, and impede provision of the improved removable, bonncts for such pipes, an ample opening is A rectangular opening is formed adjustment firmly secure the border frame der frame 10, and likewise between the outer" plate 11, the screw bolts that pass there,

lot)

, provided upon the removal of ,bonnet, so j that the'dust may be cleaned out from time to time-end the pipes rendered clean Within, thus destroying microbes that may be harbored and multiplied in the heat-conveying pipes 11.

Having thus described my invention, I claim as new, and desire to secure by Letters Patent:

1. lhe combination with a casing or the like, and a cover plate out from the casing forming an opening therein, of an inner border frame having ears thereon secured to the casing well, an outer border frame having ears secured upon the cover plate, a sealing joint ring between the cover plate and outer border frame, a sealing joint ring between the inner side of the casing wall and the inner border frame, and bolts and nuts thereon adapted for detachably securing the outer border frame and cover plate upon the outer side of the casing wall.

2. The combination with a casing or the like having an opening therein, of a frame encircling the opening on the inner side of the casing and secured thereto, the inner edge of the frame projecting beyond the edge of the opening, a cover fitting Within the opening, a frame secured to the edge of the cover and extending therebeyond and lapping on the edge of the opening, and means for detachably securing the frames together. In testimony whereof I have signed my name to this specification in the Inesence of two subscribing witnesses.

, ERICH PANNENBORG. Witnesses:

PAUL VVOLTER, FRANKLIN H. CnAse. 

